Linkage Program

There are currently two ways to show links in the Linkage software: The link is drawn as a polygon using the outer-most connectors to define the shape, and drawn as a solid object with the connector circles giving the appearance of holes within a larger polygon with rounded…

[Update: Scroll the update at the end to see new information about all of this] When I first wrote the Linkage software, I knew that if you rotate some points, that they can’t be rotated back to their original positions because of math and rounding issues. I immediately…

I have no idea why I put “elements” in “quotes” (or why the word “quotes” is in quotes) but it seemed to sort of make sense. I am still trying to figure out the best way to add the curve feature to the Linkage program. Since a curve,…

This is the first of hopefully many text tutorials for the Linkage Mechanism Designer and Simulator. Videos are great but a bit harder to make than this written stuff. Planetary gears are a set of gears where one gear rotates around another and another outer gear, always an…

I thought that the Linkage program, with the addition of external gears, would handle a planetary transmission just fine. I was wrong. Aside from the issue of having to drive this with a chain, which is necessary because making the center connector of the gear train an input…

I found a really weird sliding connector bug. If the connectors B and C are very very close to vertical but not quite exactly vertical, a math problem causes the mechanism to fail at a seemingly random position. In this case, I saw it fail about 3/4 of…

Someone contacted me asking about planetary [internal] gears. I gave it some thought and implemented it in about 2 hours. A bunch of that time was me figuring out how to automatically find the gear radii based on just the ratio. The gear with the larger ration value…

Apple did a fairly nice job with the @IBAction mechanism. It’s easy to add code to handle a menu item action in a macOS program. It’s the same with iOS for button taps and other UI actions. But with the menu items, there is a severe oversight that…

I fixed the selection box issue and the control points are included. There actually are control points associated with the line segments of the curve but they are not used and not displayed. I have been adding code to allow for editing of curves in the context of…

I did a little work last night to the node smoothing code for the end points of the Bezier curves. I also added code to handle line segments withing the compound curve. Fancier Compound Curves The first and last segments are now lines instead of curves. Notice that…